Scrutiny Debugger Demo: Live Graphing and Triggered Capture

This Scrutiny Debugger demo is a compact look at live instrumentation on an STM32 target. In a few minutes, Pier-Yves Lessard shows accelerometer variables, turns them into a continuous graph, and then sets up a trigger condition to capture a specific event in real time. For embedded developers, instead of a frozen breakpoint, we get a practical example of variable monitoring, graphing, and event capture while the firmware keeps running.

What the Demo Shows

The official project documentation frames Scrutiny as a way to plot live data, catch fast events, and inspect variables without interfering with execution, and the full Elektor webinar shows this workflow on real hardware. Here, Lessard starts with raw accelerometer data on an STM32 board and shows the values shifting as gravity moves from one axis to another when he tilts the device.

He then switches to alias variables that scale the readings into g, which makes the display more useful immediately. From there, he creates a continuous graph on the client side, starts logging, and moves the board around so the traces respond in real time. The clip also makes a useful distinction between two graphing modes. In the first, the PC interface logs what it receives. In the second, the device itself performs the acquisition, which is the more interesting option when timing matters.

Scrutiny Debugger Uses

The best part of the segment is the triggered capture. Lessard sets the embedded graph to a 1 kHz task, uses an ideal-time x-axis with 1 ms sample spacing, and defines a condition so the capture fires when the x-axis acceleration exceeds 0.5 g. He places the trigger at 75% of the graph, rotates the board, and gets an event capture that shows both the lead-up and the aftermath of the threshold crossing. That is exactly the kind of behavior ordinary polling or a halted debugger can miss.

So the Scrutiny Debugger demo is is a compact example of how live instrumentation can help with calibration, debugging, transient analysis, and test work on real embedded systems. If you deal with control loops, motor drives, robotics, power converters, or any firmware that becomes much less useful the moment you stop it, this clip is worth a look.